Coccolithophores, single - celled phytoplankton, which plays a vital role in marine biogeochemical cycling, in marine food webs and in the global climate system, has developed a variety of calcareous shells to protect itself against predation and damage. (oceanacidification.de)
To answer this question, the researchers analyzed marine sediment cores collected off Galicia (Spain) and from the Bay of Biscay, containing pollen and foraminifera, microscopic marine organisms with calcareous skeletons. (sciencedaily.com)
Ocean acidification is often considered in terms of its direct negative effects on the growth and calcification of organisms with calcareous shells or skeletons. (rstb.royalsocietypublishing.org)